Suction cleaner



June 24, 1930. w. c. DAvlnSoN SUCTION CLEANER Filed July 19. 1929 Patented n June 24, 1930 rUNITED `STATES PATENT OFFICE l WALTEB'C. DAVIDSON, OF NORTH CANTON, OHIO, ASSIGNOR TO THE HOOVER COH- IPANY, A CORPORATION 0F OHIO SUCTION CLEANER `Application filed July 19,

This invention relates tov suction cleaners ingeneral, particularly to suction cleaner dust bags. Specifically the invention relates to dust bags made from a new and improved filtering material which is characterized by its qualities as an eflicient lter for the foreign-matter-laden air which passes therethrough and by the ease of removal of the foreign' matter from the bag upon the cleaning thereof.

The object of the invention is the provision of a new and im roved dust bag for suctionv cleaners. Anot er object is to provide a dust bag for suction cleaners in which the efficiency as a. filtering medium is supplemented by the ease of removal of foreign matter collected therein. A further object of the present invention is to provide a dust bag of multi-ply material having a smooth g ossy interior.

The efiiciency of cloth dust bags as a filtering medium for the dust-ladened air which is exhausted from the suction cleaner in the operation thereof, is dependent upon the type of material used in the bag and upon the way or manner in which that material is woven into a fabric. Itis the teaching of experience that the best filtering cloth is woven from relatively rough-surfaced yarns made of loosely twisted fibers which are united into a fabric by smooth, hard yarns of relatively small diameter in order to give the resulting fabric suiiicient mechanical strength. The best grade of the ordinary filtering cloth is not too tightly woven, for such a condition results in excessive back pressure upon ythe suction cleaner and av reduction in the cleaning eliciency thereof.

On the other hand the fabric must not bel too loosely woven for in that case the air will escape therethrough carrying the foreign matter with it. is so woven that the foreign matter will be removed as thel air passes therethrough by the rough surface of the yarn going to make up that fabric, yet the fabric will not be so tightly woven as to increase excessively the p back pressure upon the suction cleaner.

"-The 4use ofyarn having a rough, harsh surface whichv is requisite for an efficient The eiiicient dust bag 1929. Serial No. 379,418.

filtering medium is accompanied by the dis-- advantage that after the foreign matter is removed from the air whichl passes therethrough it tends to adhere to the cloth and is not easily removed. The usual dust bag, being provided with an opening at one end, is cleaned by shaking the ba with the open end facing downwardly, so t at the foreign matter upon being dislodged from the surface of the cloth will fall therethrough. The resistance to elimination caused by adherence of the foreign matter to the cloth often results in failure ofremoval and the continued use of the dust bag with the foreign matter deposited thereon; an undesirable condition which results in excessive back pressure in the suction cleaner.

The present invention is characterized by the the presence, in addition to the actual ilter- Figure l is a view of a dust bag conl structed in accordance with the present invention and attached to the handle of a suction cleaner.

Figure 2 is a diagrammatical cross section of the dust bag filtering material constructed in accordance with the present invention.

Referring now to Figure 1 in particular a dust bag is 3 shownand is indicated b the reference character 3. An attaching pate 4 is secured to the lower end of the dust bag 3 which is the open end and is provided with attaching means 5 which are adapted to coact with the exhaust outlet of a suction cleaner upon which the bag is positioned to secure the lower end of the bag in place. A Supporting strap 6 is secured to the upper end of the dust bag by a pivotal connection 7 and at its upper end to the suction cleaner handle 8 through a swinging connectlon 9.

The cloth used inthe dust bag 3 1s constructed in accordance with the present infabric is indicated by the reference characwarp back yarns 16 and 17. The

ter 14 and is composed of yarns 15, 15 etc., of relatively large diameter as compared with the warp yarns and which have a rou h fibrous exterior similar in all respects to t e arns 11, 11 of the ply 10, whichk are secure together into a single ply by means of the small diameter and hard nisllied p les 10 and 14 are similar to those found in all efficient filtering material and form a coarse cloth presenting filtering texture differing in no great respect from the ordinary d ust cloth material, being composed merely of large diameter rough surface filler yarns whlch are secured together by smooth hard small diameter yarns which have no filtering qualities but merely serve to bind the material together and lend tensile strength thereto. According to the present inventlon however, the ply 18 of material of large diameter which has a smooth glossy and finished surface s uch as rayon, silk substitute formed from cellulose products or even silk itself, the yarns of which are indicated by the reference characters 19, 19, etc., is affixed to the usual plies 10 and 14. The yarns 19, 19 of the pl 18 are secured to the other two plies 10 an 14 b means of warp binder arns which are in 'cated on the drawing y the reference character 20.

The operation of the dust bag, constructed in accordance with the present invention, as a filtering medium upon the suction cleaner is as follows: The foreign-matterladen air which has been exhausted from the exhaust outlet of the suction cleaner into the dust bag at a relatively high velocity builds within the dust bag a positive pressure which is considerably higher than the atmospheric pressure on the outside of the dust bag. The air in passing from the, point of high pressure to the point of low ressure must escape through the fabric o the dust bag and 1n doing so permits the dust cloth to perform its useful function as a filtering medium. The foreign matter carried by the air ma be roughly divided into two groups, name y, fine particlessuch as dust of a small diameter and usually smooth in surface texture, and matter of relatively greater size such as lint and having a rough or coarse texture. It is the latter group which makestheo'rdinary dust bag so hard to clean because it adheres to the yarns thereof which, like themselves, are also rough. As the dirt laden air passes through the bag cloth, constructed in accordance with the present invention, it irst contacts the inner ply thereof which, as aforedescribed, comprises the yarn 19 havin the smooth glossy surface. The ply 18 being a relatively poor filter permits the smaller particles to pass therethrough but the larger.

lint particles adhere to the smooth glossy surface of the yarn 19 thereof and do not reach the plies 14 and 10. The finer particles pass through the ply 18 and are removed from the passing air by the plies 10 and 14. The lint so strenuously ad ere to the yarns of the plies 10 and 14, because of their rough exterior, thereby making the cleaning of the bag so dilicult in the usual dust bag, do not reach these plies in the dust bag constructed in accordance with the present invention but are removed by the inner ply 18.

The cleaning operation of a dust bag constructed in accordance with the present in vention is both easy and eflicient. The linty 4foreign matter which has adhered to the inner ply 18 is readily dislodged therefrom because of the smooth glossy exterior of the yarns of that ply. The smaller and finer foreign particles which have been retained by the plies 14 and 10 are not a source-of cleaning difficulty even in the usual dust bag and are easily dislodged. The ease of removal of-all the foreign particles insures a clean dust bag after each cleaning which in turn aids in the cleaning efficiency of the suction cleaner of which the bag is a part.

lit is to be understood that while a preferred embodiment of the present invention has been shown and described any changes may be made in form, construction and arrangement of the parts such as for example. the incorporation of more than two plies of the rough-surface filtering yarns or by the use of a greater number of the smooth surface lint removing yarns, without departing from the spirit of the invention or sacriicing any of the advantages thereof and the right is hereby reserved to make all such changes as fairly fall within the scope of the following claims.

ll 'claimz- 1. A filter member for use in a suction cleaner, formed of multi-ply fabric comprising a ply of material having a rough surface and a surface ply of material having a smooth surface, and warp threads uniting said plies.

2. A ldust bag for use in a suction cleaner, formed of multi-ply fabric comprising a ply of material formed of yarns having a relatively rough exteriorv and a surface ply foreign particles which ibo of material formed of yarns having a relatively smooth exterior.

3. A dust bag for use in a suction cleaner, formed of multi-ply fabric comprising an outer ply of material' having a rough surface and an inner ply of material having a smooth surface, and Warp threads uniting said plies.

4. A dust filtering member formed of multi-ply fabric comprising a plurality of plies having weft yarns with rough exteriors and a surface ply havingl weft yarns with a smooth exterior and Warp threads uniting said plies.

5. A dust filtering member formed of multi-ply fabric comprising a ply of cotton material and a surface ply' of rayon material.

6. A dust filtering material for use in a suction cleaner, formed of multi-ply fabric comprising a ply having yarns of rough eX- teriors and a. surface ply having yarns of glossy eirteriors, said plies being united by hard yarns of relatively small diameter.

Signed at North Canton, in the county ofy Stark` and State of Ohio, this 13th day of July, A. D., 1929.v

WALTER C. DAVIDSON. 

